The disposal or use of farm animal waste has become increasingly important due not only to the pollution such wastes can cause, but also to the value of such wastes as fertilizers. In barns or other feeding areas for cattle, the cattle feces and urine are ordinarily scraped into cement troughs, and the resultant semi-liquid manure is collected for eventual use as fertilizer. Such manure may be placed in compost heaps, or may be conveyed to a lagoon for storage. Lagoon storage is often desirable because the manure is often stored in a location removed several hundred yards from the barn, and because the surface of the waste material in the lagoon solidifies, rendering the lagoon substantially odorless. The semi-liquid manure slurry (hereinafter referred to as "liquid manure") eventually is pumped from the lagoon and is spread upon the ground in the usual manner.
Automatic barn cleaning devices which carry animal wastes from the barn to storage areas have been used for many years. In one device, the liquid manure is conveyed to a collection point and is then pumped, using a large, reciprocating pump, through a line leading to a storage lagoon. Manure pumps of this type often clog up because of encounters with substantially solid chunks of hay or straw or other material which becomes entrained in the liquid manure. When this happens, the pump assembly can be cleared of the obstruction only with some difficulty and waste of time. Such manure pumps, moreover, have many moving parts, and the pumping action depends upon reasonably close tolerances being maintained between the pump piston and cylinder. Because the cylinder interior is ordinarily exposed to receive liquid manure for pumping, such pumps also provide a safety hazard to one working in the immediate vicinity, and ordinarily are carefully monitored during operation.
A simple, comparatively inexpensive pump for liquid manure or other slurrys which would avoid the safety hazards and substantially constant monitoring associated with piston pumps of the type described would greatly benefit the farming industry, and is much to be desired.